The inner structure of steel-concrete components, given access to only one side, may only be examined with a significant technical effort and a great expense with regard to time The essential methods for this are radar, as well as the ultrasonic-pulse-echo methods. Common to both methods is the fact that these only permit imaged representations of the inside of the examined concrete components with multiple measurements and an extensive processing thereafter.
An ultrasonic device for the inspection of fractures or likewise is known from EP 1 415 731 A2, and this comprises a sensor with several ultrasonic elements and ultrasonic receiver elements, wherein fractures are detected on account of the received scatter echo signals.
Furthermore, an ultrasonic array with ultrasonic testing heads arranged in parallel, with ceramic tips and a resilient holder is described in RU 2 080 592 C1, wherein a part of the ultrasonic array represents transmitter elements, and a part represents receiver elements.